Simultaneous determination of formation angles and anisotropic resistivity using multi-component induction logging data
US6643589B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 5, 2002 |
| Grant date | Nov 4, 2003 |
| Priority date | — |
| Expiry date | Mar 5, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V3/28
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Measurements made by a multicomponent logging tool in a borehole are inverted to obtain horizontal and vertical resistivities and formation dip and azimuth angles of a formation traversed by the borehole. The inversion is performed using a generalized Marquardt-Levenberg method. In this generalized Marquardt-Levenberg method, a data objective function is defined that is related to a difference between the model output and the measured data. The iterative procedure involves reducing a global objective function that is the sum of the data objective function and a model objective function related to changes in the model in successive iterations. In an alternate embodiment of the invention, the formation azimuth angle is excluded from the iterative process by using derived relations between the multicomponent measurements.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.